Patent GB-863040-A (GB)
Title: Improvements in vitamin preparations
IPC: A61K31/59
Filed: 1958-06-10
Abstract: Dry, free-flowing, finely-divided stable preparations of fat-soluble vitamins or other oxygen-sensitive active ingredients of fodder compositions are produced by emulsifying the ingredient in an aqueous solution of a polyvinyl alcohol at a temperature above the melting point of the ingredient and well above the gelling temperature of the polyvinyl alochol, cooling and at least partially drying the emulsion in the form of a spray of fine particles or droplets, collecting the partially dried particles and completing the drying to the desired degree at a low temperature, e.g. 35 DEG C.  The cooling and partial drying may be effected by spraying of the emulsion from a cool region into a chamber of hot air, by spraying into a bath of acetone or other water - extracting organic liquid, or by spraying on to a stationary or moving bed of powdered starch, preferably through a cloud of air-borne starch particles above the bed; calcium stearate may be added to the starch powder to increase its resistance to wetting by water.  According to an example (Example 1), 5g. of a Vitamin A or D3 oil was emulsified in a solution at 80 DEG C. of 20g. of polyvinyl alcohol (97% hydrolysed) in 80 ml. of distilled water; the emulsion was added to 120 ml. of a mineral oil of suitable viscosity and stirred well to give a polyphase emulsion in which the mineral oil was the continuous phase.  The polyphase emulsion was cooled to about 3 DEG C. to gel the beadlets of vitamin-containing polyvinyl alcohol and was then slowly poured into a column of acetone cooled to the same temperature.  The solidified beadlets collected at the foot of the column were finally dried in a current of warm air. In another example (Example 3), a small proportion of a low viscosity alginate, e.g. sodium alginate, was added to the aqueous solution of polyvinyl alcohol, the use of mineral oil being dispensed with.ALSO:Dry, free-flowing, finely-divided stable preparations of fat soluble vitamins or other oxygen-sensitive active ingredients of food compositions are produced by emulsifying the ingredient in an aqueous solution of a polyvinyl alcohol at a temperature above the melting point of the ingredient and well above the gelling temperature of the polyvinyl alcohol, cooling and at least partially drying the emulsion in the form of a spray of fine particles or droplets, collecting the partially dried particles and completing the drying to the desired degree at a low temperature, e.g. 35 DEG  C. The cooling and partial drying may be effected by spraying of the emulsion from a cool region into a chamber of hot air, by spraying into a bath of acetone or other water-extracting organic liquid, or by spraying on to a stationary or moving bed of powdered starch, preferably through a cloud of airborne starch particles above the bed; calcium stearate may be added to the starch powder to increase its resistance to wetting by water.  According to an example (Example 1), 5 g. of a Vitamin A or D3 oil was emulsified in a solution at 80 DEG  C. of 20 g. of polyvinyl alcohol (97% hydrolysed) in 80 ml. of distilled water; the emulsion was added to 120 ml. of a mineral oil of suitable viscosity and stirred well to give a polyphase emulsion in which the mineral oil was the continuous phase.  The polyphase emulsion was cooled to about 3 DEG  C. to gel the beadlets of vitamin-containing polyvinyl alcohol and was then slowly poured into a column of acetone cooled to the same temperature.  The solidified beadlets collected at the foot of the column were finally dried in a current of warm air.  In another example (Example 3) a small proportion of a low viscosity alginate, e.g. sodium alginate, was added to the aqueous solution of polyvinyl alcohol, the use of mineral oil being dispensed with.